Wool Keratin based electrospun biotextiles: recent advances for in vitro applications

Wool waste derived Keratin (WK) is a highly multifunctional and sustainable biopolymer serving various roles in nature due to its multiple properties, wide spectrum of structural designs and impressive performance. Due to their ingenious structuring and tunability across many length scales, keratins may inspire natural structures with tailored properties (i.e., biocompatibility, degradability, stiffness) specifically addressed to mimic cell interface and the extracellular matrix of natural tissues. Their peculiar properties in solution enable the easy processing of WKs via the electrospinning technique to form nanofiber assemblies suitable for the fabrication of innovative biotextiles. Electrospinning is emerging as an eco-friendly and cost-effective manufacturing process that allows the generation of micro and/or sub micrometric sized fibers by applying high voltage generated electrical forces on selected polymer solutions. In the last decade, the use of this technique was widely used in the production of randomly/uniaxially oriented fibers for biomedical applications, due to the peculiar morphological cues of obtained fibers - i.e., high surface area to volume, fully interconnected void structure - that allow efficiently supporting cell adhesion, proliferation and migration. Herein is an overview of our recent studies focused on the use of electrospinning to fabricate WK based nanofibers with multiple ionisable side chains to improve cell interactions.